The present invention relates to a dispenser for apportioned dispensing of material, in particular, pasty masses, having a piston which travels within the dispenser storage chamber in the direction towards a mouthpiece, in accordance with the actuating steps, and a slide which is displaceable by an actuating handle in the direction towards the mouthpiece. A lip sealingly guides the slide to the dispenser housing. The slide also has a wing which, upon the actuation stroke, comes against the wall of an ejection channel in a sealing manner. Upon a return slide the wing lifts away from the wall.
A dispenser of this type is known from West German OS No. 29 16 206. In that case the slide is guided in an ejection channel which is arranged transverse to the storage chamber. The storage chamber and ejection channel are in flow communication via a passageway. The slide which delivers the apportioned quantity has, on its mouthpiece side, a wing in the form of an annular cuff. The latter is oblique so that a ring-funnel which widens in the direction of delivery is present. By acting on an actuating handle associated with the slide, the separated portion which lies in front of the wing is forced out through the opening of the mouthpiece. The pressure which is thus produced displaces a valve, which otherwise closes the mouthpiece opening, out of its closed position. This valve is a centrally located plug-like closure piece which is urged in closing direction by a spring. Upon the pressing out of the portion, the piston of the storage chamber, which follows in the direction towards the mouthpiece corresponding to the actuating steps, is pulled along. The slide is furthermore sealed off by a lip lying on the other side of the passageway. This lip moves along the wall of the ejection channel and, like the cuff forming the wing, is of annular shape. After the dispensing of the apportioned quantity, the slide moves back under spring action into its basic position. The wing in this connection moves over the mass lying behind it, releasing its sealed application against the corresponding wall of the ejection channel and therefore moving somewhat radially inward. After reaching the basic position, the wing again moves out into its blocking position. This apparatus is not only too difficult to produce as a mass-production article, but it also requires a precision which is excessively great for a mass-production article. In this regard, the rigidity of the wing must be adapted to the force of the valve spring. If for example the valve spring is too hard then the rigidity of the cuff collapses. There will then be disturbances in the dispensing delivery. If, on the other hand, the rigidity of the cuff is made greater, it no longer travels over the mass which is to be pulled along next. The function depends too greatly on the degree of viscosity of the mass. From a structural standpoint, furthermore, the transverse position of the ejection channel with respect to the storage chamber is disadvantageous insofar as problems in injection molding arise there. Furthermore, finally, the number of parts is too great.
The object of the present invention is to develop a dispenser of this type which is simpler to manufacture and more advantageous to use in the manner that, on the one hand, a special valve on the mouth side can be dispensed with while the filling column nevertheless is retained free of interruption until the delivery of the last portion, and all of this with considerably fewer parts in such a dispenser.